Metal chair construction



Nov. 24, 1942. N. c. GILKISON METAL CHAIR CONSTRUCTION Filed May 6, 1959 2 Sheets-Sheet l Nov. 24, 1942. N. c. GILKISON METAL CHAIR CONSTRUCTION Filed May 6, 1939 2 Sheets-Sheet 2 Patented Nov. 24, 1942 T oFFIcE mar. cmim consrnucrron j Norman 0. Gllkison, uni-u, om, mi The corporation of Ohio Application 8, 1939, Serial No. 272,261

This invention relates to metal furniture and more particularly to metal chairs. 4

Prior metal furniture constructions have involved stamped or otherwise formed metal backs and seats-and tubular frame construction but such prior metal furniture has been relatively unsatisfactory in service for various reasons including buckling of chair backs, improper drainage provision incorporated in chair seats and awkward association of the frame to the chair back, chair seat, and other parts of the frame and users of such prior constructions have felt ill at ease and insecure.

It is an object of the instant invention to provide a metal chair which lends itself to mass production and capable of giving lasting satisfactory service.

A further object ofthe invention is to provide a novel metal chair seat and back combination which peculiarly lends itself to mass production and simultaneously eliminates buckling in the chair back and efl'ects drainage of the chair seat.

It is a further object of the instant invention to provide a secure novel frame construction and an association of such frame with the chair seat and chair back capable of lasting satisfactory service.

Other objects and the nature and advantages.

of the invention will be apparent from the following description taken in conjunction with th accompanying drawings, wherein:

Fig. 1 is a view in perspective of a metal chair in accordance with the invention;

Fig. 2 is a rear elevational view of one-half of the chair in Fig. 1;

Fig. 3 is a. side elevation of the chair in Fig. Fig. 4 is a vertical section taken along line 4t of Fig. 1 and lookingin the direction of the arrows;

Fig. 5 is a detail view in perspective of a portion of the rear of the chair showing the association of the combination armrest and frame with the chair back and-the relationship of the chair seat to the chair back;

Fig. 6 is a view in perspective similar to Fig. but of a modified form of chair; I

Fig. '7 is a plan view of a stamping which may serve either as a chair seat or chair back;

Fig. 8 is a view similar to Fig. 7 of a stamping as in Fig. 'l but formed to be used as a chair seat; and

Fig. 9 is a view similar to Fig. 5 but illustrating the association'of parts of the chair in Fig, 6.

Referring to Figs. 1 to 5 inclusive and Figs. 7

22 supported by vertical frame members 23, which frame members are tied atjtheir lower horizontal generally flat portions 24 by lateral bars 25 and bolts 1). The vertical frame members are secured along their upstanding portions 26' adjacent the front comers of the seat 22 by angle brackets .21, as best illustrated in Figs. 2 and 3. The rear ends 28 of the arm portions 28 of the vertical frame members 23 are secured to the rearwardly extending flanged portions Ill of the chair back It by brackets II, as best illustratedin Figs. 1 and3.

To further reinforce the frame members, angular brace 32 is securedto the inner side'ofthe downwardly turned front portion of the seat 22 by the bolts 33 to effect a truss-like'construction with a portion of the seat front acting as a member of the truss.

The chair .back 2| is fabricated of a stamping, such. as illustrated in Fig. 7, having a major planular area 34, rearwardly turned side flanges 30. and arearwardly turned upper head portion 35. The planular area 34 is formed withvertical grooves 38 which not only serve to add strength to this relatively large metal area but in addition act to take up measurable-excess metal in this area which occurs when the stamping including the rearwardly turned portions is fabricated. were it not for this metal take-up provision, the excess metal in the chair back would buckle under the weight of a users back. Ac- H cordingly, applicant's novel metal take-up deformations not only permit the use of a thinner metal in a chair back thereby permitting the stamping to be made by lighter machinery and of less expensive raw stock, but at the same time eliminates buckling due to the presence of excess metal which is very objectionable in a chair back. When utilizing the stamping illustrated inFig. 7 as a chair back, the lower portion 31 thereof which has no rearwardly extending side portions is itself bent'rearwardly, as-.i1lustrated in Fig. 5, and engages the rear portion of the upper area of the seat 22.

The chair seat 22 is fabricated from a stamping identical to the on from which the chair back is made, but instead of bending the lower portion 31 *rearwardly, a' little larger area I! is cut off to efl'ect the chair seat 22 illustrated in Fig. 8. The vertical grooves It in the chair seat effect a triple function; namely. they serve as drainage means to convey moisture of! of the chair which is particularly advantageous when a chairis in use outdoors, and in addition the two and 8, a chair Ill comprises a back It and a seat functions attributed to the vertical metal take- .up deformations in the chair back, i. e., they take up excess metal thereby preventing buckling in the chair seat and simultaneously strengthen the chair seat permitting a lower cost stock to be utilized in the fabrication of the seat. The particular drainage feature is best illustrated in Figs. and 8 wherein the grooves in the chair seat are shown to be continuous to the rearmost portion of the seat and extend across the bottom side of the rearwardly extending portion 31 of the chair back 2|. The rearwardly extending portion 31 of the chair back- 2I may be secured to the rearmost portion of the chair seat 22 by four bolts 39, see Figs. 2 and 5. It is to be noted that by utilizing the same die for both the chair seat and the chair back, the graceful turned head portion of the stamping may serve as the head portion of the chair back 2| and the front portion of the seat 22 which engages the inner side of the user's legs thereby contributing to the comfort of the user while obviating otherwise necesary additional operations on thestampings.

The chair back 2| and seat 22 may be fabricated of a metal inherently resistant to the weather, or painted, or otherwise decorated as desired.

The vertical frame members 23 are fabricated of flat metal strips which are bent into the shape illustrated by a cold process. The chair depicted in Fig. 1 by its very nature is capable of deflnite spring action which is attributable to the process by which the frame members are fabricated. Previously, in the making of similar frame members in order that the finished frames have the required spring, they were heated dur- Ing their formation and then permitted to cool retaining the shape given them in their heated condition. The applicant has found that by utilizing a large press such as a "bulldozer" the frame members may be formed cold without loss of resiliency, or with even better resiliency which assures a most desirable spring action in the completed chair.

It will be appreciated that metal chairs in accordance with the instant invention are to be fabricated simply and inexpensively and accordingly novel means is provided to'permit of simple assembly of the rear portions 28 of the vertical frame members 23, see Fig. 5, with the rearwardly turned side portions 30 of the chair back 2|. Accordingly, to prevent shear or tearing action in the wall of the rearwardly turned portion 30 due to stress being transmitted by the weight of the user through the bolt 4| which passes through the bracket 3|, reinforcing means which may comprise a pair of strips 42 and 43 are associated with the inner face of the rearwardly turned portion 30 and may be of the same or similar material to that in the back 2 I. Both the rearwardly turned portion 30 and the reinforcing strips 42 and 43 may be drilled at 44 and to permit of adjustment of the resilient vertical frame members 33 as required by the user without fear of shearing or tearing of the relatively thin metal in the rearwardly turned portion 30 of the chair back 2|. The strips 42 and 43 not only tend to strengthen the rearwardly extending portion 30 against shearing or tearing action but by being tied thereto by the bolt 4I they serve in eifect as a frame mounted on the inner side of the back 2| and strengthen the major planular area of the chair back 2| in the same manner that a pictureframe supports a picture mounted therein.

Referring to the modified form of construction illustrated in Figs. 6 and 9, the chair back 2| and seat 22 may be identical with that described in connection with the chair depicted in Fig. 1 with the exception of the bracing thereof at the junction between the vertical frame and the chair back, the junction between the chair back and the chair seat. and the reinforcing against lateral sway at the front portion of the seat and at an intermediate portion in the vertical frame members. In this chair the vertical frame members I23 may comprise generally U-shaped tubes. the rear ends of the upper rearwardly extending portions I23 of which are secured to the rearwardly .extending flanges 30 of the chair back 2| by'a bolt- I4I, see Fig. 9. The generally horizontal lower legs I24 of the vertical frame members I23 are secured together by a U-shaped tubular connecting member I23 which telescopes with the open end of the legs I24. Simple bolt means bb secure the member I 25 to the legs I24. To prevent side sway or insecurity in the chair additional bracing means for the frame is provided at the front corner portion of the seat. The generally upstanding portions I28 of the vertical frame members I23 are secured to the front portion of the seat by simple bolts I21 and short angularly disposed tie members I23 are secured to both the front portion of the seat 43 and the upstanding portions I23 of the vertical frame members I23 whereby a truss-like construction is efiected involving the front portion 40 of the seat as a member of the truss and a relatively rigid construction results. The applicant has found that this truss-like construction is essential when th telescopic junction is utilized to laterally tie the ends of the legs I24 of the vertical frame members I23. It is to be noted that the vertically depending front 40 of the chair seat 22 serves ideallyas an attaching portion for the member I23, obviating the necessity of any auxiliary bracket means or the like and that the truss construction involves simply the addition of th members I23 utilizing all otherwise necessary members, i. e., the vertical frame members I23 and the seat 22, as members of the trusses.

It is conceivable that the rear bracing construction associated with the ends I23 of the vertical frame members I23, the rearwardly extending flanges 30 of the chair back 2|, the rearwardly extending flange 31 of the chair back and the rearmost portion of the seat 22 be similar to that illustrated in Fig. 5, but the applicant has found that the construction illustrated in Fig. 9 is sometimes better suited. In this modification the reinforcing strips I42 and I43 respectively are generally L-shaped; the lower legs of the L's cooperating with the rearwardly extending flange 31 of the back 2| to provide additional bracing or framing" of the chair back 2|. The rearwardly extending flange 30 and the reinforcing members I42 and I43 may be drilled at I44 and I45 to provide for adjustment of the vertical frame members I23 to give the resiliency required by the user of the chair.

In order to bend the flat bars 23 forming the side frames for chairs as illustrated in Fig. 1, it is essential that bar steel of proper carbon content be selected, if the bending is to be effected without heat treatment and inherent resiliency result. In practice it has been found that the carbon content of bar steel to be used in the above process is between .60 and .75" and the specifications for the steel should further include a maximum phosphorous content of .05, a maximum sulphur content of.05,

and a silicon content of about .15.? The content of the various ingredients are indicated herein in the numerical scale well known in the trade. v

Not only is it essential that the spring steel have specifications in accordance with the above, but in order that the resiliency desired be assured, the bar should be bent properly. When the bar is bent slowly, the proper resiliency characteristics result. When the bar is bent quickly,

the molecular rearrangement iri the inner and outer sides of the bar do not have time to take place and the bar breaks. It has been found in practice that bars 1 inches wide and inch thick may be bent to a radius of from 2 or 3 inches to a much larger radius with the press operating not materially faster than 1 stroke every fifty seconds. It is preferred to effect 2 bends in the bars, see Fig. 1, one having a 4 inch clude ordinary bolts, such as screws and nuts,-

rivets and the like.

' It will be obvious to those skilled in the art that various changes may be made in this device without departing from the spirit of the invention and therefore the invention is not lim- .7

ited to what is shown in the drawings and described in the specification but only as indicated in the appended claims.

What is claimed is:

1. A metal chair comprising a back and seat formed of sheet metal stampings, the seat stamping having side flanges and a front down-turned marginal edge and a rear unflanged edge and the back stamping having angular rearwardly extending flanges at its opposite side and bottom marginal edges and a rearwardly turned marginal edge portion at the top, the bottom flange of the back being seated on and secured to the unflanged rear edge of the seat, a pair of frame members one at each side of the chair. said frame members each having vertically extending portions. and rearwardly extending upper and lower portions defining, respectively, arm rests and base members for the chair, means connecting the arm rest portions to the side flange portions of the back and means securing the vertically extending portions of said frames to the front portion of the seat, said seat being formed with one-or ,more reinforcing grooves extending longitudinally thereof to reinforce and lend rigidity to these'at, at least one of said grooves extending to the rear unflanged edge of I the seat to effect drainage ofwater or excess moisture from the seat at the point where the bottom flanged edge of the back engages the rear edge of the seat.

2. A metal chair comprising a back and seat formed of sheet metal stampings having marginal side flanges, the rear edge of said seat being unflanged and the lower edge of said back being formed with a flange which rests on the rear unflanged edge of the seat, a pair of side frame members having front substantially vertical por tions and upper and lower rearwardly extending portions respectively defining arm rests and base members orrunners for the chair, said vertical port ons being securedto the side flanges of the seat, means connecting the rear ends of the arm rest portions to the marginal side flanges of the back, said seat being formed with one or more reinforcing .grooves extending longitudinally thereof to reinforce and lend rigidity to the seat, at least one of said grooves extending to the rearmost edge of the seat beneath thebottom flange the rear edge of the seat with the lower flanged -edge of the back,

NORMAN c. GILKISON. 

